The AO3401 is also labelled as A19T in its components surface. This MOSFET is a P-channel Low voltage type. It is comes in SOT-23 SMD packaging. This article shares the AOT3401 Pinout, equivalent MOSFETS List for replacement and its key characteristic’s and features.
What is the AO3401 MOSFET?
- Low voltage P-channel MOSFET.
- Comes in SOT-23 SMD packaging.
- Drain-source voltage of 20V and continuous drain current of 4 to 4.3 Ampere.
- Gate drive voltage is about below 2.5V.
AO3401 MOSFET Pinout
Pinout Configuration
| Pin No. | MOSFET Pin |
|---|---|
| 1 | Gate (G) |
| 2 | Source (S) |
| 3 | Drain (D) |
Understanding the Function of Each AO3401 Pin (Gate, Source, Drain)
This SMD MOSFET has three pins which are Gate, Drain and Source. The MOSFET is act like a switch when the gate voltage receives the MOSFET conduct the current flow from Drain to source. But the flow get stopped if their is no enough gate voltage get in the Gate pin of the MOSFET.
AO3401 Electrical Specifications and Ratings
- Type is P-channel
- SOT-23 SMD packaging.
- Drain to source voltage is -30V
- Continuous Drain current is 4 to 4.2A
- Internal on Resistance is equivalent to 0.52 milliohms
Equivalent MOSFETS List for Replacement
| Part Number | Drain-Source Voltage | Continuous Current | On-Resistance |
|---|---|---|---|
| AO3401 (Original) | -30 V | -4.0 A | 52 milliohms |
| AO3401A | -30 V | -4.3 A | 44 milliohms |
| DMG3415U | -20 V | -4.0 A | 42 milliohms |
| IRLML6402 | -20 V | -3.7 A | 65 milliohms |
✔ Always check the specifications and pinout of component before replacing with original components.
Common AO3401 Failure Symptoms and Troubleshooting Tips
- In the condition of internal short, the MOSFET remain permanently ON and multimeter shows short circuit in Drain – source pins.
- The MOSFET does not switch ON if the supplied voltage is Insufficient for the set gate voltage or damaged MOSFET.
- In case of Higher voltage drop across MOSFET due to the Increased RDS(ON) due to degradation, so you should Measure the Drain-Source voltage drop and replace if necessary.
- Intermittent or unstable switching happens due to Weak solder joints or gate noise. to solve this you need to Inspect soldering and stabilize gate drive signals.
Applications of AO3401 MOSFET
- In battery protection circuit this MOSFET can be used for reverse polarity and over current while charging in lithium ion batteries.
- Switching DC loads with low power loss.
- USB power management circuits.
- Commonly found in smartphones, tablets, and battery powered gadgets.
